Textbook-Integrated Guide to Educational Resources

TIGER

A New "Bottom-Up" Framework for Teaching Chemical BondingTami Levy Nahum, Rachel Mamlok-Naaman, Avi Hofstein, and Leeor KronikThis article presents a general framework for bonding that can be presented at different levels of sophistication depending on the student's level and needs. The pedagogical strategy for teaching this model is a "bottom-up" one, starting with basic principles and ending with specific properties.Levy Nahum, Tami; Mamlok-Naaman, Rachel; Hofstein, Avi; Kronik, Leeor. J. Chem. Educ.2008, 85, 1680.

Acid-Catalyzed Enolization of β-TetraloneBrahmadeo Dewprashad, Anthony Nesturi, and Joel UrenaThis experiment allows students to use 1H NMR to compare the rates of substitution of benzylic and non-benzylic a hydrogens of -tetralone and correlate their findings with predictions made by resonance theory.Dewprashad, Brahmadeo; Nesturi, Anthony; Urena, Joel. J. Chem. Educ.2008, 85, 829.

More on ClO and Related RadicalsWilliam B. JensenThe novel Lewis structure for the ClO radical and other related 13e isoelectronic species presented by Hirsch and Kobrak is identical to that proposed by Linnett over 40 years ago for the same species on the basis of his well-known double-quartet approach to Lewis structures.Jensen, William B. J. Chem. Educ.2008, 85, 783.

Ionic Bonding |

Lewis Structures |

Free Radicals

Six Pillars of Organic ChemistryJoseph J. MullinsThis article focuses on a core set of conceptselectronegativity, polar covalent bonding, inductive and steric effects, resonance, and aromaticitythe proper application of which can explain and predict a wide variety of chemical, physical, and biological properties of molecules and conceptually unite important features of general, organic, and biochemistry.Mullins, Joseph J. J. Chem. Educ.2008, 85, 83.

Bioorganic Chemistry |

Covalent Bonding |

Hydrogen Bonding |

Mechanisms of Reactions |

Periodicity / Periodic Table |

Reactive Intermediates |

Resonance Theory

Lewis Structure Representation of Free Radicals Similar to ClOWarren Hirsch and Mark KobrakAn unconventional Lewis structure is proposed to explain the properties of the free radical ClO and a series of its isoelectronic analogues, particularly trends in the spin density of these species. Hirsch, Warren; Kobrak, Mark. J. Chem. Educ.2007, 84, 1360.

Aromatic Bagels: An Edible Resonance AnalogyShirley LinDescribes a classroom demonstration involving the use of a bagel and cream cheese as an analogy for benzene that emphasizes the deficiencies of using a single Lewis structure to describe this structure.Lin, Shirley. J. Chem. Educ.2007, 84, 779.

Let Us Give Lewis Acid–Base Theory the Priority It DeservesAlan A. ShafferThe Lewis concept is simple yet powerful in its scope, and can be used to help beginning students understand reaction mechanisms more fully. However, traditional approaches to acid-base reactions at the introductory level ignores Lewis acid-base theory completely, focusing instead on proton transfer described by the Br?nsted-Lowry concept.Shaffer, Alan A. J. Chem. Educ.2006, 83, 1746.

Acids / Bases |

Lewis Acids / Bases |

Lewis Structures |

Mechanisms of Reactions |

Molecular Properties / Structure |

VSEPR Theory |

Covalent Bonding |

Brønsted-Lowry Acids / Bases

More on the Nature of ResonanceRobert C. KerberThe author continues to find the use of delocalization preferable to resonance. Kerber, Robert C. . J. Chem. Educ.2006, 83, 1291.

Aromatic Compounds |

Covalent Bonding |

Molecular Properties / Structure |

Resonance Theory |

Nomenclature / Units / Symbols

More on the Nature of ResonanceWilliam B. JensenSupplements a recent article on the interpretation of resonance theory with three additional observationsone historical and two conceptual.Jensen, William B. J. Chem. Educ.2006, 83, 1290.

Lecture Templates: Convenient Partial Lecture Delivery SystemElzbieta Cook and Robert L. CookReports on the use of two forms of PowerPoint lecture presentationsa complete version used by the lecturer and a corresponding partial version available in advance to students. Pre-prepared lecture presentations allow for the sharing of lecture materials among teaching faculty and ensure consistency among several lecture sections in team taught courses.Cook, Elzbieta; Cook, Robert L. J. Chem. Educ.2006, 83, 1176.

If It's Resonance, What Is Resonating?Robert C. KerberThis article reviews the origin of the terminology associated with the use of more than one Lewis-type structure to describe delocalized bonding in molecules and how the original usage has evolved to reduce confusionKerber, Robert C. . J. Chem. Educ.2006, 83, 223.

The Concept of Oxidation States in Metal ComplexesDirk SteinbornAfter a brief historical survey, basic considerations are given to assign oxidation numbers of atoms in molecules on the basis of their Lewis structures by splitting shared electrons in covalent bonds heterolytically. Advantages over the frequently used method to assign oxidation numbers by using a set of hierarchical rules are demonstrated for some nonmetal compounds. Assignment of oxidation numbers of metals is systematically worked out for metal complexes with n-, pi-, and s-ligands. Furthermore, it is shown how the concept of oxidation states is embedded in the teaching process of molecular chemistry for early chemistry students. Steinborn, Dirk. J. Chem. Educ.2004, 81, 1148.

The Molecular Model GameStephanie A. MyersStudent teams must draw Lewis structures and build models of various molecules and polyatomic ions; different team members have different responsibilities.Myers, Stephanie A. J. Chem. Educ.2003, 80, 423.

How We Teach Molecular Structure to FreshmenMichael O. HurstExamination of how textbooks discuss various aspects of molecular structure; conclusion that much of general chemistry is taught the way it is for historical and not pedagogical reasons.Hurst, Michael O. J. Chem. Educ.2002, 79, 763.

Lewis Structures in General Chemistry: Agreement between Electron Density Calculations and Lewis StructuresGordon H. PurserThe internuclear electron densities of a series of X-O bonds (where X = P, S, or Cl) are calculated using quantum mechanics and compared to Lewis structures for which the formal charges have been minimized; a direct relationship is found between the internuclear electron density and the bond order predicted from Lewis structures in which formal charges are minimized.Purser, Gordon H. J. Chem. Educ.2001, 78, 981.

Lewis Structures Are Models for Predicting Molecular Structure, Not Electronic StructureGordon H. PurserThis article argues against a close relationship between Lewis dot structures and electron structure obtained from quantum mechanical calculations. Lewis structures are a powerful tool for structure prediction, though they are classical models of bonding and do not predict electronic structure. Purser, Gordon H. J. Chem. Educ.1999, 76, 1013.

Molecular Properties / Structure |

Covalent Bonding |

Computational Chemistry |

Quantum Chemistry |

MO Theory |

Learning Theories |

Lewis Structures |

Molecular Modeling

The "Big Dog-Puppy Dog" Analogy for ResonanceTodd P. SilversteinIn this analogy, puppy dogs are restricted to a specific dog run; they represent s-bond electron pairs. Big dogs are allowed to roam freely over several consecutive dog runs; they represent delocalized p-bond electron pairs. By adding a bunny rabbit who is chased by the big dog, the analogy can be expanded to account for delocalized formal charge in a resonance hybrid. Silverstein, Todd P. J. Chem. Educ.1999, 76, 206.

Covalent Bonding |

Learning Theories |

Resonance Theory |

Molecular Properties / Structure

Simplified Lewis Structure Drawing for Nonscience MajorsBarnabe B. MiburoLewis structures are drawn using a simplified novel method with the following features: 1) the atoms used are brought in carrying all their valence electrons; 2) bonds are created by pairing up valence electrons between the central atoms and peripheric atoms; 3) anions are formed by addition of electrons to single electrons on appropriate atoms, while cations are formed by removal of single electrons.Miburo, Barnabe B. J. Chem. Educ.1998, 75, 317.

Do our students really understand the Hammett equation? Schwan, Adrian L.In this author's experience, many students can proceed through text questions dealing with the Hammett equation without having a full understanding of the Hammett analysis. He offers a question that enables students to gain a better appreciation of this concept.Schwan, Adrian L. J. Chem. Educ.1993, 70, 1001.

Chemometrics |

Resonance Theory |

Constitutional Isomers

Writing Lewis structures Weeks, DanielIn response to a problem posed in a June 1991 article, this author points to a solution he authored 17 years ago.Weeks, Daniel J. Chem. Educ.1993, 70, 519.

Explaining resonance - a colorful approachAbel, Kenton B.; Hemmerlin, William M.An analogy using color to help students understand that a resonance molecule does not shift back and forth between Lewis Structures, but is in fact a hybrid of the two structures.Abel, Kenton B.; Hemmerlin, William M. J. Chem. Educ.1991, 68, 834.

Structure-resonance theory for pericyclic transition statesHerndon, William C.The purpose of this article is to show that structure-resonance theory can be used to understand the effects of structure or substituents on the rates of thermal pericyclic reactions.Herndon, William C. J. Chem. Educ.1981, 58, 371.

Resonance theory and the enumeration of Kekule structuresHerndon, William C.The formulation of resonance theory as it is practiced today is explicated in the well-known books by Pauling and Wheland. Study of these texts show that resonance theory are so drastic that many theoreticians are loathe to ascribe validity to the less rigorous method.Herndon, William C. J. Chem. Educ.1974, 51, 10.

Dewar resonance energyBaird, N. C.In the present paper, some of the general properties of the Dewar Resonance Energy definition are developed. In particular, the DRE value for a compound is shown to be independent of the numerical values used to bond energies, and the use of DRE in judging the aromaticity of organic molecules is illustrated.Baird, N. C. J. Chem. Educ.1971, 48, 509.

Electronic interactions between nonconjugated groupsFerguson, Lloyd N.; Nnadi, John C.The purpose of this paper is to discuss some of the different molecular systems in which electronic interactions between classically nonconjugated groups are explicable in terms of molecular orbital theory as well as nonclassical resonance theory.Ferguson, Lloyd N.; Nnadi, John C. J. Chem. Educ.1965, 42, 529.

MO Theory |

Resonance Theory |

Molecular Properties / Structure

Rules for molecular orbital structuresMeislich, HerbertIn view of the fact that molecular orbital theory makes more correct predictions and avoids the misconceptions that arise in the minds of novice students when they are exposed to resonance theory, it would be better to use M.O. theory as much as possible in teaching organic chemistry.Meislich, Herbert J. Chem. Educ.1963, 40, 401.